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btr0cur.c Improve range size estimate for big ranges

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ha_innobase.cc	Fix Sort aborted bug


sql/ha_innobase.cc:
  Fix Sort aborted bug
innobase/btr/btr0cur.c:
  Improve range size estimate for big ranges
BitKeeper/etc/logging_ok:
  Logging to logging@openlogging.org accepted
This commit is contained in:
unknown 2001-08-09 20:41:20 +03:00
parent 83fbd8d8db
commit 5ea83eed34
3 changed files with 48 additions and 5 deletions
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1
BitKeeper/etc/logging_ok
View File

@ -1 +1,2 @@
jani@hynda.mysql.fi
heikki@donna.mysql.fi

11
innobase/btr/btr0cur.c
View File

@ -2351,6 +2351,7 @@ btr_estimate_n_rows_in_range(
btr_path_t* slot1;
btr_path_t* slot2;
ibool diverged;
ulint divergence_level;
ulint n_rows;
ulint i;
mtr_t mtr;
@ -2393,6 +2394,7 @@ btr_estimate_n_rows_in_range(
n_rows = 1;
diverged = FALSE;
divergence_level = 1000000;
for (i = 0; ; i++) {
ut_ad(i < BTR_PATH_ARRAY_N_SLOTS);
@ -2403,6 +2405,13 @@ btr_estimate_n_rows_in_range(
if (slot1->nth_rec == ULINT_UNDEFINED
|| slot2->nth_rec == ULINT_UNDEFINED) {
if (i > divergence_level + 1) {
/* In trees whose height is > 1 our algorithm
tends to underestimate: multiply the estimate
by 2: */
n_rows = n_rows * 2;
}
return(n_rows);
}
@ -2417,6 +2426,8 @@ btr_estimate_n_rows_in_range(
return(10);
}
divergence_level = i;
diverged = TRUE;
} else if (diverged) {
n_rows = (n_rows * (slot1->n_recs + slot2->n_recs))

41
sql/ha_innobase.cc
View File

@ -822,11 +822,11 @@ ha_innobase::open(
if (NULL == (ib_table = dict_table_get(norm_name, NULL))) {
fprintf(stderr, "\
Cannot find table %s from the internal data dictionary\n\
of InnoDB though the .frm file for the table exists. Maybe you have deleted\n\
and created again an InnoDB database but forgotten to delete the\n\
corresponding .frm files of old InnoDB tables?\n",
fprintf(stderr,
"Cannot find table %s from the internal data dictionary\n"
"of InnoDB though the .frm file for the table exists. Maybe you have deleted\n"
"and created again an InnoDB database but forgotten to delete the\n"
"corresponding .frm files of old InnoDB tables?\n",
norm_name);
free_share(share);
@ -2659,6 +2659,37 @@ ha_innobase::records_in_range(
DBUG_RETURN((ha_rows) n_rows);
}
/*************************************************************************
Gives an UPPER BOUND to the number of rows in a table. This is used in
filesort.cc and the upper bound must hold. TODO: Since the number of
rows in a table may change after this function is called, we still may
get a 'Sort aborted' error in filesort.cc of MySQL. The ultimate fix is to
improve the algorithm of filesort.cc. */
ha_rows
ha_innobase::estimate_number_of_rows(void)
/*======================================*/
/* out: upper bound of rows, currently 32-bit int
or uint */
{
row_prebuilt_t* prebuilt = (row_prebuilt_t*) innobase_prebuilt;
dict_table_t* ib_table;
DBUG_ENTER("info");
ib_table = prebuilt->table;
dict_update_statistics(ib_table);
data_file_length = ((ulonglong)
ib_table->stat_clustered_index_size)
* UNIV_PAGE_SIZE;
/* The minimum clustered index record size is 20 bytes */
return((ha_rows) (1000 + data_file_length / 20));
}
/*************************************************************************
How many seeks it will take to read through the table. This is to be
comparable to the number returned by records_in_range so that we can